Metallizing device



Aug. 24, 1937. w, STEVENS 2,091,021

METALLIZING DEVICE Filed June 23, 1954 3 Sheets-Sheet 1 INVENTOR. WILLIAM H-STEVEMS I9 ATTORNEY Aug. 24, 1937. w. H. STEVENS METALLIZING DEVICE Filed June 23, 1934 3 Shee ts-Sheet 2 INVENTOR. WILLIAM H. STEVENS ATTORNEY 3 Sheets-Sheet 55 Ddu- 9. 1- W PM M Illa/l4,

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INVENTOR. WILLIHM H- STEVENS BY Q4 gm? ATTORNEY W. H. STEVENS 'METALLIZING DEVICE 7 Filed June 25, 1934 Aug. 24, 1937.

Patented Aug. 24, 1937 UNITED STATES PATENT O'Brien 2,091,021 I ME'lALLIZING nnvrcn Application June 23, 1934, Serial No. 732,095

8 Claims.

The invention relates to a means for effecting the metallic coating or impregnation of a. surface whereby to metallize the latter,- and more specifically concerns the type of metallizing unit F in which a coating material is melted and discharged as .a spray, said unit arranged for free manual manipulation in the manner of a gun or Pistol.

An object of the invention is to providea par- Hzlcularly simple and effective control means for the air blast and fuel supply for the nozzle of a metallizing pistol of the class described.

Another object is to provide-for the mixing of a combustion-supporting gas with a combustible gas at a point in the .pistol structure which is least subject to variations in temperature, whereby to insure the provision of a uniform fuel 1 mixture at the nozzle. 1

A further object is to provide a simple and particularly effective pre-mixing means for the fuel gases.

An additional object is toprovide a combina tion fuel nozzle and wire guiding structure in which the heat emanating from a torch flame ;beyond the forward nozzle end is so distributed that fusible wire being fed therethrough to said flame may not be melted within the nozzle.

Yet another object is to provide a metallizing V pistol which is adapted for universal use to fuse.

3 and project the material of wires of difiering composition and/or size merely by the replacement of a single nozzle portion or element.

Added objects are to provide certain refinements relating to the wire-feeding mechanisms of metallizing pistols whereby to increase the efficiency of operation and use of such devices.

111a invention possesses other objects and fea-.

hm of advantage, some of which, with the foregoing, will be set forth or beapparent in the fol-" Figure 2 is a left-side view of the pistol, a por tion of the handle thereof being shown insectlon at the plane of the line 2-2 in Figure 1. Figure 3 is-a rear elevation. of the pistol.

. .Figure is a right-side elevation of the pistol;

with the nozzle assembly removedand with its handle shown in section at the plane of the line i H in Figure 1.

Figure 5 is a section of the handle taken at 5-5 in Figure 1.

Figure 6 is a top plan .view of the handle.

Figure 7 is an enlarged and partly sectional top plan view of the structure, a cover element being removed and the sectional portions of the showing being. taken atthe plane of the nozzle axis.

Figure 8 is an enlarged axial section through a fuel nozzle assembly of the structure. I Figures 9 and 10 and 1-1 are enlarged transverse sections at 99, l0-l0,-and ll--H respectively in Figure 7. 1

Figure 12 is a front view of the central body. member of the pistol with the nozzle and handle 1 removed.

Figure 13 is a section taken through aside wall of the body substantially at l3l3 in Figure 12.

Figure 1a is a section takenthrough the fr ont wall of the body at Ill-J4 in Figure 13.

Figure 15 is a section at the broken linel5-l 5 in Figure 12, 7

Figures 16 and 1'1 are transverse sections at the lines I6|6 and l'| l |respectively in .Fig-

ure 15. V

Figure 18 isa top plan view of the body,.the cover element therefor' being removed and a" wire-feeding means being inoperative with respect to a wire extending through the body.

Figure 19 is a plan section-at l9-l9 in Fig-'- ure 12.

Figure 20 is a plan section at20- -20 in Figme 12. p I

Figure 21 is an enlarged view of a portion of tion are incorporated in the structure of a metallizing pistol I having a body portion 2, a nozzle structure 3 at the front of the body and from which a spray of atomized material is arranged to be directed toward a surface to be treated, and

a handle 4 by which a manual support and manlpulation of the device is facilitated. The present metallizing pistol provides a torch flame at its nozzle for melting awire 5 which is composed of a fusible material to'be deposited, said wire passing through suitable guideways in the body atomization and projection as a spray.

The fuel for the torch flame may advantageously comprise a proper mixture of a combustion-supporting gas and a combustible gas, and the present unit has been specifically designed for the production and use of an oxy-acetylene torch flame for melting the wire. The wire-feeding mechanism essentially comprises a'pair of feed rollers 6 and l cooperative-to grip the wire between them and arranged for rotation by means of a suitable pneumatic motor. Also, an air blast is provided and utilized at the nozzle to complete the required supply of oxygen for the torch flame and to atomize and project the molten material to be sprayed.

Besides providing ameans by which the present pistol may -be manually supported and manipulated-me handle 4 is also conveniently utilized to provide inlet ducts for the introduction of air and oxygen and acetylene gas to the pistol structure. As particularly brought out in Figures 2, 4, 5 and 6, longitudinal ducts 9 and 9 and I0 are provided in the handle, said ducts being respectively arranged for connection at the free handle end with sources (not shown) of compressed air and oxygen and acetylene. .Normally closed valves II and I2 are respectively interposed in the ducts 9 and I, said valves including stems l3 andwhich extend from the handle at its forward side. A branch air duct l5 extends from the upper handle end to a juncture with the-duct 3, and the duct |5 has a normally closed valve l6 operative therein and provided with a stem H which extends from the forward handle side.

A lever member I9 is pivoted to the handle at its forward side and for a rocking movement against the protruding ends of the various valve stems to open the valves controlled thereby. Since the member I8 is designed for use in actuating all of the valves, the valve stems l3 and H and H preferably emerge from the handle in mutual adjacency; as shown, the valves and their -mutually parallel stems are equally spaced apart.

The valves may be of any suitable structure; spring-pressed poppet valves are shown.

A spring catch I9 is provided at the lower handle end for releasably engaging the lower end of the member I8 to secure the same in valve-opening position with respect to the valves, it being noted that the member I9 is arranged for an initial valve-opening actuation thereof by the hand of a person grasping the handle to support and direct the unit, and that the catch I9 is adapted to engage the handle when the valves are all in open condition. In this manner, a continued operation of the metallizing pistol is provided for independently of the continuance of the grip of the operators hand; such a functioning of the catch is shown in Figure 4.

The duct I5 is utilized to supply the air for the nozzle blast and its valve I6 is preferably opened last as the member I8 is rocked to open the various valves. Preceding an opening of the air valve is, the respective acetylene and oxygen valves l2 and H are opened in succession, it being noted that the valve stems l4 and I3 and [1 are of such lengths that the member l9 may engage them in the indicated order as the member is element having lateral flanges 2| at its upper end I for usein attaching it tothe under side of the V body element 2. At their lower ends, the ducts ous side and end walls of the cavity.

coupling connections in mutually parallel rela- 5 tion facilitates the grouping of the hoses as in a single line. The ducts 9 and 9 and Ill and I5 terminate at a flat face 22 at the other end of the handle element, the latter being brought out in Figure 6.

The body 2 has an open top and comprises a bottom wall 23, right and left side walls 24 and 25 respectively, a front wall 29, and a rear wall 21. A cover plate 23 is hinged to the body at the top of the front wall 26 for normal disposal to close the body cavitywhile providing for access to its interior as may be required. As illustrated, a cylindric boss 29 extends integrally and forwardly from an upper point of the front wall 26 and is utilized in mounting the nozzle assembly 3 on the body. The body cavity is divided slightly below the axial line of the nozzle by means of a partition plate 3| which is secured to asupporting flange 32 extending integrally from the vari- Ducts 33 and 34 and 35 and '36 are provided in the bottom body wall 23, said ducts each start ing from the lower face of the body for the registration of their intake ends with the discharge ends of the handle ducts 9 and 9 and I0 and I5 respectively, reference being made to the showing ofFigure 20 of the drawings. The duct 33 is designed to conduct air to'the motor which operates the feed rollers 6 and and the duct 36 is con-- tinued through the front body wall 26 and the boss 29 to supply air for the nozzle blast. The ducts 34 and 35 terminate at a mixing chamber 31 which comprises a portion of a uniform cylindric bore 38 extending into the bottom wall 23 from the front face of the body. 4

An element 39 is removably mounted in the bore 39, said element terminating between the discharge points of the ducts 34 and 35 and having spaced inner portions 49 and 4| closely fitting the bore 38. An outer end portion 43 of 43 the element 39 is expanded and threaded'to engage in a correspondingly expanded and threaded outer portion of the bore 38, and the extreme outer end portion of the element is formed as a head 44 by which the element may 5| be engaged for mounting it or dismounting it with respect to its operative disposition in the bore 39. v I

The part of the element 39 between its portions 49 and 4| is of reduced diameterand is 5 arranged to be disposed opposite the discharge end of the duct 34 whereby it defines an annular manifold space 45 thereat. Also, the element portion between the portions 4| and 43 is reduced to define the mixing chamber 31 previous; 6 1y referred to, said chamber being of annular cross-section. Grooves 46 are provided in the portion 4|, said grooves extending spirally about the portion and connecting the chamber 31 with the space 45 whereby fluid discharged through 6 the grooves 46 will enter the chamber 31 in a spiralling stream thereof.

By particular reference to Figures 21 and 22, it will be noted that the element 39 is provided with an axial boreextending from its inner end 7 to at least the inner end portion of the chamber 31, and that ports 41 extend radially from said bore to the outer face of the element at a'point of the latter at the inner end of the chamber 31. In this manner, acetylene gas entering the 7 bore 38 from the duct 35 may flow through the central bore of the element 38 and discharge radially into the spiralling stream of oxygen in the chamber 31. A discharge duct 88, shown in Figures 8 and 12 and 14, leads upwardly through the front body wall 26 from the forward end of the chamber 31 and to the forward face of the body boss 28.

The disclosed arrangement for mixing a combustion-supporting gas (oxygen) with a combustible gas (acetylene) has been found to insure an even mixing of the gases in providing a fuel for delivery to the torch nozzle through the duct 48. Furthermore, the location of the mixing chamber 31 in the bottom wall of the body whereby it is spaced from both the nozzle and handle insures a constant temperature at the mixing chamber whereby the uniformity of composition of the fuel mixture may be further assured, the supply pressures for the various gases being assumed to be constant.

As is particularly brought out in Figures 12 and 16 and 19, the motor means of the device comprises a rotor 58 disposed in a complementary cavity 5| which extends within the body and from the side wall 24. The rotor 50 is provided with radial vanes 52 against which an impelling stream of air may impinge for effecting an actuation of the rotor. As shown, the propelling air jet is arranged to issue from a nozzle duct which comprises the discharge portion of the duct 33 and directs a stream transversely against successive rotor vanes 52 in a plane centrally ofthe vanes and transverse to the rotor axis. A needle valve 49 is operative in the duct 33 for controlling the supply of air to the rotor, the stem of said valve extending from the rear face of the body and being provided with a knob for facilitating its manual setting to provide for the operation of the motor at a desired speed.

A plate 53 provides an outer closure for the cavity 5| and is perforated to permit the discharge of the motor-operating air from the cavity. For permitting access to the motor parts, the plate 53 is removably mounted in its place.

The rotor 50 is mounted on a shaft 54 which is journalled in anti-friction bearing assemblies 55 and 56 which are mounted respectively in the inner wall of the cavity 5| and the body side wall 25. Preferably, and as shown, the center of the bearing 55 lies in the before-mentioned plane of operation of the air jet which actuates the rotor, this arrangement being particularly important as a means of minimizing motor vi-. bration effects, it being noted that the rotor 58 is designed for operation at a relatively high speed. A thrust bearing assembly 51 is mounted in the plate 53 for engaging the opposed end of the shaft 54, said shaft carrying a worm 58 and being so rotated that the reaction of the worm 58 against a gear 59 on an intermediate shaft 68 is exerted against the'bearing 57.

The shaft 68 is disposed below the shaft 54 andis journalled in and between suitable bearings 6| mounted in the front and rear body walls 28 and 21. Toward its forward end the shaft 60 carries a worm 62 which engages a gear 63 on a shaft 64 which extends upwardly from a suitable bearing assembly 65 n the bottom wall 23 and through a bearing assembly 66 in the partition 3|. The shaft 64 carries the feed roller 5 for rotation therewith whereby an appropriate feeding of the wire 5 to tne nozzle 3 may be effected when the described motor means is actuated.

It will be understood that the described operative connections between the feed roller 8 and the I partition from thelubricant; the arrangement is understood to insure a proper lubrication of the gearing and bearings at'all times.

By particular reference to Figures 7 and to 18 inclusive, it will be seen that the feed roller 1 is rotatable about a pin 68 which depends from a rocker member 89 which is pivoted to the partition for rotation about an axis which is parallel to the axis of the shaft 84 and is eccentrio to the latter axis. The arrangement, it is noted, permits a swingingof the roller I to and from an engagement with the wire 5; when the wire is not engaged by the roller 1, the roller 6 is inoperative to advance the wire even if it is rotating.

Means are provided for resiliently and releas ably holding the roller I in its operative position at the will of the operator of the metallizing pistol, andsaid means is arranged to be conveniently controlled in accordance with the disposition of the body cover 28. Accordingly, the rocker member 69 is provided with an extending spring arm 'II for such engagement with a member I2 mounted on the under side of the cover 28 that the roller I is pressed against the wire 5 to grip the wire between the rollers 6 and 1 whenever the cover is in its operative position. The member I2 is conically tapered whereby it may wedgedly engage the spring arm II to rock the member 69 from a position such as that shown in Figure 18 to the position shown in Figure 7 as the cover is moved into place. i

A catch I3 is provided for securing the cover 28 in its operative position, said catch being shown as shaped in a spring bar and having an upper and free extremity disposable beneath the cover for holding the same in a partly open position while the wedge member I2 is inoperative with respect to the member 69. In this manner, an operator may stop the feeding of the wire merely by lifting the cover, as to the supported position on the top of the catch element I3 as is indicated in Figure 15. The present arrangement is also understood to adapt the device to the feeding of wires of different sizes without involving a replacement of parts.

Gears I6 and 11 may be mounted on the shaft 64 and pin 68 respectively for rotation with the rollers 6 and 'I thereat, said gears meshing only when the roller I is operatively disposed against a wire; in this manner, the wire may be posi-- tively driven forward by both rollers.

Preferably, andas shown, the wire 5 is extended through a tubular guide member I4 which is mounted in the rear body wall 21 and extends forwardly to a point adjacent the rollers 6 and 'I and in thelinc of the nozzle axis. The guide tube I4 is preferably belled out at its rearward end whereby wire entering its bore may not become sharply bent or kinked thereat even though the wire is fed into the guideway at an angle; a preferred shape for the inlet end of the guide member is disclosed in the showing of Figure 7-.

As disclosed in detail in Figures 7 to 11, the nozzle assembly comprises an inner torch nozzle having mutually coaxial rear and front sections 18 and 19 respectively, and a hood enclosing the torch nozzle and having rear and front sections and 8| respectively, said hood sections being cooperative to provide an air-blast passage about and along the torch nozzle. The cylindric body boss 29 which mounts the members 18 and 80 is provided with a threaded axial bore which is continued to the body cavity, is externally threaded, and has a planar forward face 82 at which the air duct 36 and fuel duct 48 both terminate.

The nozzle section 18 is provided with a reduced and threaded rearward portion 83 which engages in the threaded bore of the boss 29 for fixing a planar radial rear face 85 of the section in sealed engagement with the boss face 82.

An annular manifold groove 84 is provided in the face 85, said groove registering with the outlet of the fuel duct 48 for receiving fuel therefrom.

At its forward end, the section 18 is'provided with an annular face having an annular manifold groove 86 therein. Ducts 81 connect the grooves 84 and 86 through the section.

An axial bore 88 is provided in the section 18, and said bore is enlarged and threaded at its forward end portion to receive a rearward stem extension 89 of the front nozzle section 19, said section comprising the tip element of the torch nozzle. At the forward end of the stem 89, the nozzle member 19 is provided with a bearing face for sealed registration with the front end face of the section 18, and the former face is shown as provided with a manifold groove 9| registering with the groove 86. While the opposed grooves 86 and 9| cooperatively provide an annular manifold space between the nozzle sections 18 and 19, it will be obvious that one of said grooves might be'omitted if desired.

A stepped axial bore 92 is provided in the nozzle section 19, said bore having its largest (counterbore) portion at its forward end. A tubular lining member 93 is fixed in the bore 92, said member being provided with a radial flange portion 94 which tightly fits the front part of the enlarged forward portion of the bore 92 and thereby defines an annular chamber 95 behind it in such bore portion. Ducts 96 connect the chamber 95 with the manifold chamber provided by the grooves 86 and 9|, three of such ducts being provided in the present instance. The bore of the lining member 93 is contracted at its forward end portion to closely engage with and about a wire 5 for guiding and centering the same as it emerges axially from the nozzle, said bore freely receiving the wire except at said contracted extremity.

Equally spaced ducts 91 extend forwardly through the flange 94 from the chamber 95 and toward a common point in the nozzle axis whereby they are cooperative to provide mutually convergent fluid streams which may be ignited to jointly provide a conical torch flame into which the wire is advanced for fusion thereat. The apex angle of the flame cone is preferably of the order of sixteen degrees.

Externally thereof the nozzle tip section 19 is conically tapered and the forward portion of the side surface thereof is provided with a. plurality of grooves 98 which are directed toward a point slightly in advance of the torch flame point, said grooves being arranged to direct an atomizing and propelling air blast against the material which has been melted from the wire.

It will now be noted that the .hood is generally tapered and extends somewhat beyond the forward end of the nozzle tip member 19. The rearward hood section 80 threadedly engages about the body boss 29 for fixed mounting thereon, and the rearward end of the front hood section 8| threadedly engages with and about the forward end of the section 80 for adjusted disposal therealong. The hood, it will be noted, defines a closed space of annular cross-section about and along the torch nozzle assembly, and the air supply duct 36 discharges into the rear end of said space. Opposite the nozzle tip grooves .98, the tapered bore of the forward hood portion BI is complementary to the tip surface and may be adjustably spaced therefrom by shifting it in its threaded mounting on the section 80. As shown, a lock-nut 99 is provided on the threaded end of the section 80 for locking, the section 8| in such adjusted relation to the nozzle tip that the atomizing and projection of the melted wire material may be most efiiciently effected.

The present nozzle assembly is particularly adaptable for use with wires of different sizes and/or composition merely by substituting another nozzle tip member 19 to suit. For the more readily fused materials such as lead and aluminum, the torch flame need not be so hot for a given size of wire, while for a larger wire of a given material more heat would be required. It will therefore be understood that substitute nozzle tips 19 might have fewer or more ducts 91, larger or smaller ducts 91, or larger or smaller wire guiding bores at the nozzle tip. Also, the rate of feed for wires of different size and/or composition may-be varied to a proper value through adjustment of the needle valve 49 which controls the air supply to the motor.

Through the provision of the relatively small fuel manifold chamber 95 as close as possible to the nozzle tip, temperature conditions thereat are substantially constant and below an excessive value while preheating the fuel therein. Furthermore, while the nozzle section 19 would be of a relatively hard metal of relatively low conductivity for heat, the lining member is preferably formed of copper, a material which has a relatively high heat conductance, whereby heat radiated rearwardly from the torch flame is most freely distributed rearwardly through the nozzle and wire and largely to the air blast stream in the hood. In this manner, neither the nozzle nor I wire may become sufficiently heated tomelt the same'when the metallizing pistol is in use; in fact, the disclosed arrangement has been found so effective that the wire is not melted in "the nozzle bore even if its forward feeding is stopped while the torch is lit.

From the foregoing description taken in connection" with the accompanying drawings, the advantages of the construction and method of use of the described device will be readily understood by those skilled in the art to which the present invention appertains. While I have described the features and the principles of operation of a device which I now consider to be a preferred embodiment of my invention, I desire to have it understood that the specific showing is primarily illustrative, and that such changes may be made, when desired, as fall within the scope of the following claims.

I claim:, 1. In a metallizing pistol of the type described.

a hollow body and wire-feeding mechanism therein, a gas torch nozzle carried by said body, a handle element arranged for grasping to support the pistol and to direct its discharge, said 5 handle provided with mutually independent longitudinal ducts therethrough for the passage of a combustion-supporting gas and a combustible gas through the handle, a gas duct in said nozzle discharging therefrom, a closed gas duct traversing the wall portion of said body and discharging into said nozzle duct, closed ducts traversing the wall portion of the body and connecting said handle ducts with said first body duct, means whereby the combustion-supporting gas'is discharged into said latter duct in a spiralling stream, means whereby the combustible gas is discharged radially into said spiralling stream of combustion-supporting gas, and valves operative in said handle ducts as the sole, means of controlling the fluid fiow through the said ducts and to the nozzle tip.

2. In a metallizing pistol of the type described,

means defining a closed gas mixing chamber spaced from the pistol nozzle and of annular cross-section, a duct connecting said chamber with the pistol nozzle, a duct to supply a combustion-supporting gas to said chamber, means whereby said combustion-supporting gas may be discharged spirally into said chamber, a duct to supply a combustible gas to said chamber, and

means whereby said combustible gas may be discharged radially into said chamber and the stream of combustion-supporting gas therein.

3. In a metallizing pistol of. the type described, a hollow body having an open side and containing a wire feeding mechanism, a fluid-actuated motor in said body for operating the said mechanism and comprising a cylindric rotor having radial vanes, a duct in the body for discharging fluid against the rotor vanes in a plane centrally of the vanes and transverse to the axis of rotation of the rotor for actuating the latter, and bearings for the rotor operative in said plane. 4. In a metallizing unit of the type described, a forward nozzle portion having a stepped axial bore with the larger bore portion at its forward end,-a tubular lining element arranged to receive a wire for fusion and fittedly engaged in the bore of said nozzle portion and having a radial flange at its forward end fittedly engaging solely the forward part of the enlarged bore portion to define therein an annular manifold chamber, a duct extending rearwardly from said chamber for connection with a source of gaseous fuel, and equally spaced ducts through said flange directed toward a common point in the nozzle axis forwardly of the nozzle tip whereby to supply gaseous fuel from said chamber to supply a flame at said point. i 5. In a metallizing unit of the type described, a forward nozzle member having a stepped axial bore with the larger bore portion at the forward end of the bore, a tubular lining element fittediy engaged in the bore of said nozzle member and having a radial flange at its forward end radially fitting the larger bore portion and spaced from the inner end of the latter to define an annular fed forward for fusion at said flame, said lining element being composed of a material having a higher heat conductance than the material of the nozzle member which carries it.

6. In a metallizing pistol of. the type described, means to premix a combustion-supporting gas with a combustible gas and comprising a cylindric bore in the pistol body; a member having end portions and an intermediate portion closely fitting said bore and being circumferentially reduced between said portions to define supply and mixing chambers of annular cross-section in the bore space thereat, grooves extending spirally in the outer face of said intermediate portion of the member to connect said chambers whereby a gas may be directed spirally into the mixing chamber from the supply chamber, and a duct axially traversing said member and terminating at radial ports in the member which discharge into the portion of the mixing chamber which is adjacent the spirally grooved portion of the member; a duct terminating at said supply chamber and arranged to convey a combustion-supporting gas thereto; a duct connecting with the duct of the member and arranged to convey a combustible gas thereto for radial discharge into the mixing chamber through the aforesaid ports; and a discharge duct for the mixing chamber.

7. In a metallizing pistol of the type described, a hollow body having an open upper side, a wirefeeding mechanism comprising cooperatable rollers operative in a plane parallel to that of said open body side and between which a wire in the pistol is arranged to be gripped for its advancement through the pistol, fixed guide members constantly engaging the wire at both sides of said rollers for retaining the wire in a fixed line in said plane, a planar partition mounted in said body below said rollers and guide members and cooperative with the side and bottom walls of the body to define a closed chamber for receiving and retaining a lubricant, a motor on said body, drive connections for the motor and rollers disposed in said chamber and including a shaft extending through the partition and mounting a said roller, means supporting the other roller for its adjustment with respect to the wire and the first roller, and means to dispose and resiliently retain the rollers in wiregripping relation.

8. A structure in accordance with claim 7 wherein the means supporting the second mem- 

